ArticleOriginal scientific text

Title

Ideals of finite rank operators, intersection properties of balls, and the approximation property

Authors 1, 2

Affiliations

  1. Department of Mathematics, Agder College, Tordenskjoldsgate 65, N-4604 Kristiansand, Norway
  2. Faculty of Mathematics, Tartu University, Vanemuise 46, EE-2400 Tartu, Estonia

Abstract

We characterize the approximation property of Banach spaces and their dual spaces by the position of finite rank operators in the space of compact operators. In particular, we show that a Banach space E has the approximation property if and only if for all closed subspaces F of c0, the space ℱ(F,E) of finite rank operators from F to E has the n-intersection property in the corresponding space K(F,E) of compact operators for all n, or equivalently, ℱ(F,E) is an ideal in K(F,E).

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Pages:
175-186
Main language of publication
English
Received
1998-05-11
Accepted
1998-08-24
Published
1999
Exact and natural sciences